CalorimeterEndcapLayers and InnerDetectorLayers are both sonifications using real 7 TeV collisions data.

CalorimeterEndcapLayers is a group of 8 notes, each note corresponding to a layer in the endcap of the ATLAS calorimeters. These layers are the presampler, three layers of electromagentic endcap calorimeter and four layers of hadronic endcap calorimeter. The energy deposited in each layer is mapped to the pitch, vibrato speed, attack and resonance.

In the InnerDetectorLayers example, there are 4 notes corresponding to the four inner sub-detectors; the b-layer, the pixel detector (PIX), the semiconductor tracker detector (SCT) and the transition radiation tracker (TRT). The last note in the sequence is consistently much higher than the others because its pitch is mapped to the number of TRT hits, which is always quite large. This is because the TRT detector is made from thousands of drift tubes, making it possible for alot of hits to be recorded. The other sub-detectors don't record as many hits, but those they do record have their positions measured extremely precisely.

EventMonitor is an example sonification of our first attempt to tackle real time data. At the LHC there are millions of collisions per second. Not all of these events can be captured for analysis, there are just too many! We decide which events to capture based on a simple device known as the trigger. The kinds of events we want to capture have certain signatures; for example an isolated track or two jets of particles moving in opposite directions. There are several different triggers for the different physics groups, but one that is important to everybody is known as the minimum bias trigger. This trigger doesn't pick out events that look special, it just picks them at regular time intervals and asks that they have at least one inner detector track.

For this example we have taken the data events passing the Minimum Bias trigger in real collisions. The time between events (notes) is stretched out and the pitch of each note is determined by the number of tracks in the event.

The timing of the notes in this example is not regular because the data was taken when the detector was just starting up with below-optimal energy and luminosity, so many events do not have a track passing the momentum threshold for acceptance and the trigger is not fired.

You can download the breakpoint file (time: number of tracks) used to make this example by clicking on the button on the right. If you make your own sounds with this, we'd love to hear from you!